1. Field of the Invention
The present invention relates to an apparatus for inspecting mechanical strength of bottom portions of bottom-closed hollow pipes. For example, this apparatus may be used to inspect mechanical strength of bottom portions of bottom-closed hollow pipes made of zirconia and having the bottoms closed with the same material at one end.
2. Related Art Statement
Although the above ceramic-closed hollow pipe are used, for example, as constituent members for cells, no bottom portion strength-inspecting apparatuses have been formerly known which could accurately inspect strength of a bottom portion of the bottom-closed hollow pipe of this type. Strength of bottom-closed hollow pipes have been inspected by applying pressure inside the hollow pipe. However, it is difficult to inspect the strength of the bottom portion, because when high pressure is applied to the interior of the slender bottom-closed hollow pipe, a side wall is first broken. However, when such slender bottom-closed hollow pipes are used as constituent parts for fuel cells, they are often broken due to lack in strength at their bottom portions thereby posing a practical problem.